J/MNRAS/522/3124ivo://CDS.VizieR/J/MNRAS/522/3124doi:10.26093/cds/vizier.75223124CDSQuintana A.L.Wright N.J.Jeffries R.D.2024-08-22T20:17:15Z2023-05-31T18:11:09ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frstellar-associationsob-starsvisible-astronomytrigonometric-parallaxastrometryproper-motionsstellar-agesstellar-distanceOB associations are important probes of recent star formation and Galactic structure. In this study, we focus on the Auriga constellation, an important region of star formation due to its numerous young stars, star-forming regions, and open clusters. We show using Gaia data that its two previously documented OB associations, Aur OB1 and OB2, are too extended in proper motion and distance to be genuine associations, encouraging us to revisit the census of OB associations in Auriga with modern techniques. We identify 5617 candidate OB stars across the region using photometry, astrometry and our SED fitting code, grouping these into five high-confidence OB associations using HDBSCAN. Three of these are replacements to the historical pair of associations - Aur OB2 is divided between a foreground and a background association - while the other two associations are completely new. We connect these OB associations to the surrounding open clusters and star-forming regions, analyse them physically and kinematically, constraining their ages through a combination of 3D kinematic traceback, the position of their members in the HR diagram and their connection to clusters of known age. Four of these OB associations are expanding, with kinematic ages up to a few tens of Myr. Finally, we identify an age gradient in the region spanning several associations that coincides with the motion of the Perseus spiral arm over the last ~20Myr across the field of view.2023MNRAS.522.3124Qhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/522/3124CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/350 : Gaia EDR3 (Gaia Collaboration, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/522/3124https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/522/3124http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/522/3124https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/522/3124https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/522/3124http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/522/3124GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/522/3124/aur (Daya for the 5617 identified OB stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/522/3124/aur?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/522/3124/aur?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/522/3124/aur?GETtext/xml+votable180.050000true80.3290619432.134938060.0055555555555555563/20 4/84 1530-1531 5/344-346 352-353 356-357 6114-6115 6118-6119 6128 6130 6136 6138-6139 6/1388 1390 1416-1417 1420-1421 1432 1472-1473 1476 24287 24309 24311 24317 24466-24467 24469-24471 24516 24518 24524 24526 24548 24550-24551https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/522/3124?format=asciiOpticaldefaultJ/MNRAS/522/3124/aurDaya for the 5617 identified OB stars_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.raindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGaiaEDR3Gaia EDR3 source identification numbermeta.id;meta.mainRA_ICRSBarycentric right ascension of the source (ICRS) at Ep=2016.0 (ra)degpos.eq.ra;meta.mainDE_ICRSBarycentric right ascension of the source (ICRS) at Ep=2016.0 (dec)degpos.eq.dec;meta.mainPlxAbsolute stellar parallax of the source at the Ep=2016.0maspos.parallaxfloatlogTeffP1616th percentile logarithm of the SED-fitted effective temperature from the posterior distributionlog(K)phys.temperature.effectivefloatlogTeffP8484th percentile logarithm of the SED-fitted effective temperature from the posterior distributionlog(K)phys.temperature.effectivefloatlogLumMedMedian logarithm of the SED-fitted luminositylog(solLum)phys.luminosityfloate_PlxStandard error of the stellar parallax at Ep=2016.0masstat.error;pos.parallaxfloatpmRAProper motion in right ascension pmRA*cosDE of the source in ICRS at Ep=2016.0mas/yrpos.pm;pos.eq.rafloate_pmRAStandard error of proper motion in right ascension directionmas/yrstat.error;pos.pm;pos.eq.rafloatpmDEProper motion in declination direction of the source in ICRS at Ep=2016.0mas/yrpos.pm;pos.eq.decfloate_pmDEStandard error of proper motion in declination directionmas/yrstat.error;pos.pm;pos.eq.decfloatpmlProper motion in Galactic longitude direction at Ep=2016.0mas/yrpos.pmfloate_pmlStandard error of proper motion in Galactic longitude directionmas/yrstat.errorfloatpmbProper motion in Galactic latitude direction at Ep=2016.0mas/yrpos.pmfloate_pmbStandard error of proper motion in Galactic latitude directionmas/yrstat.errorfloatlogTeffMedMedian logarithm of the SED-fitted effective temperaturelog(K)phys.temperature.effective;stat.medianfloatlogLumP1616th percentile logarithm of the SED-fitted luminosity from the posterior distributionlog(solLum)phys.luminosityfloatlogLumP8484th percentile logarithm of the SED-fitted luminosity from the posterior distributionlog(solLum)phys.luminosityfloatlogMassMedMedian logarithm of the SED-fitted masslog(solMass)phys.massfloatlogMassP1616th percentile logarithm of the SED-fitted mass from the posterior distributionlog(solMass)phys.massfloatlogMassP8484th percentile logarithm of the SED-fitted mass from the posterior distributionlog(solMass)phys.massfloatAVMedMedian extinction in the V-bandmagphys.absorptionfloatAVP1616th percentile of the extinction in the V-bandmagphys.absorptionfloatAVP8484th percentile of the extinction in the V-bandmagphys.absorptionfloatDistMedMedian SED-fitted distancepcpos.distanceintDistP1616th percentile SED-fitted distance from the posterior distributionpcpos.distanceintDistP8484th percentile SED-fitted distance from the posterior distributionpcpos.distanceintAssoc[12345n] Association assigned to each starmeta.id.parentchar